Your Fix Ends Soon: How to Approach a Buy-to-Let Remortgage in Late 2026

If your buy-to-let fix ends in the next six months, the numbers underneath it have moved since you last checked them, and not in your favour. Swap rates and gilt yields have climbed hard since the start of September, best-buy tables are only now catching up, and the "wait for rates to fall" instinct that made sense back in June is a weaker bet today. This is a practical look at where pricing actually stands and how to approach the decision, not a recommendation to fix, track, or pick any specific product.

Where Pricing Actually Is

Fixed-rate buy-to-let mortgages are priced off swap rates and gilt yields, not Bank Rate, and both have moved a long way this month. The five-year swap rate, one of the main reference points lenders use for BTL pricing, rose from around 4.16% in early August to 4.36% on 3 September, then pushed through 4.5% as the month went on, touching its highest level since October 2023.

Gilt yields tell the same story. The 10-year gilt yield hit 5.295% on 10 September, the highest since August 2007, and was still trading at 5.35% on 24 September. The 30-year yield sat at 5.83% the same day, having earlier touched levels last seen when the Debt Management Office was selling 30-year bonds at its costliest rate since it was founded in 1998. None of this is Bank Rate moving. The Bank of England held at 3.75% again on 17 September, a 6-3 vote, with the next full decision and Monetary Policy Report not due until 5 November.

Moneyfacts' overall average fixed buy-to-let rate stands at 5.47%, unchanged since 1 August. That headline stability hides more movement underneath it: the two-year and five-year splits have climbed to 5.29% and 5.66% respectively as of 1 September, and both have kept edging up since. Keep those two measures separate. The 5.47% figure describes the whole market. The 5.29%/5.66% split describes two specific products, and it's the one moving.

Frequently Asked Questions

Should I start my buy-to-let remortgage early if my fix ends in the next six months?

Most lenders let you reserve a rate three to six months before your current deal ends, and many will move you onto a lower rate if one appears before completion. With funding costs having moved sharply against borrowers since early September, starting early gives you a hedge against further rises without giving up the chance of a better deal later. It isn't advice to rush into any specific product.

What buy-to-let mortgage rate should I use to plan my numbers in late 2026?

Moneyfacts puts the overall average fixed buy-to-let rate at 5.47%, unchanged since 1 August 2026, while its two-year and five-year splits have kept climbing, reaching 5.29% and 5.66% at the start of September. Best-buy tables show lower headline rates, but carry arrangement fees running into five figures, so they show direction rather than what you'll actually pay once fees are weighed in.

What ICR stress test do buy-to-let lenders use?

Most lenders in 2026 stress your rental income against a 5.5% floor rate, regardless of the actual product rate on offer. On top of that floor, basic-rate taxpayers and limited company borrowers typically need rent to cover 125% of the stressed interest, higher-rate taxpayers in personal name need 145%, and additional-rate taxpayers can face up to 167%.

How many buy-to-let mortgages are maturing in the second half of 2026?

Barclays' analysis of CACI Mortgage Market Database figures puts buy-to-let maturities at £23.3 billion across July to December 2026, with July the busiest month at £4.8 billion and August the quietest at £2.8 billion. The often-quoted figure of 1.8 million fixed-rate mortgages expiring in 2026 is a UK Finance whole-market estimate covering all mortgage types, not a buy-to-let-specific number.